The parents of two young children, whose mentally ill aunt literally carried them to their deaths on a Lowell highway in 2008 have sued McLean Hospital in Belmont, alleging that the hospital was negligent in treating the woman, Marcelle Thibault, 39, whose actions killed the children and herself.

Ken and Danielle Lambert, of Brentwood, New Hampshire, argue in the complaint filed in Suffolk Superior Court that the renowned Massachusetts psychiatric hospital provided negligent care to Danielle Lambert’s identical twin sister, Marcelle Thibault, and is therefore legally responsible for the wrongful deaths of their 5-year-old daughter, Kaleigh, and 4-year-old son, Shane. Thibault, the children’s aunt, was also was killed on Jan. 11, 2008, when she intentionally carried the children into high-speed traffic on Interstate 495 in Lowell. Following the deaths of their children and Thibault, the Lamberts told the Boston Globe that psychiatrists had diagnosed Thibault with bipolar disorder in September 2007 and discharged her six days later after prescribing psychotropic drugs and outpatient therapy.

However, the couple said, doctors at McLean never told family members about the risk Thibault might pose to herself or others. It is this failure that will form the basis of the plaintiffs’ suit against McLean Hospital. Two McLean psychiatrists and a licensed social worker are also named as defendants in the suit: Dr. Matthew E. Bernstein, Dr. Mia D. Pfleging and social worker Kathryn Healey. The plaintiffs are fundamentally arguing that these professionals breached the legal duty owed to them as family members, by not warning them of the risk of suicidal ideation (thoughts,) in Thibault, or at the very least warning persons such as themselves that Thibault could pose a risk of harm to herself or others. The Lamberts contend, naturally, that had they been made aware of this risk by the defendants, they never would have placed their children in the care of Thibault that night, and that this breach of duty caused their children’s wrongful death.

When commenting to the media later in 2008, the Lamberts said they thought they had no reason to worry when Thibault arrived at their house about 8 p.m. on the night the deaths occurred, to pick up Kaleigh and Shane to sleepover at her Bellingham house. According to the Lamberts, Thibault had been discharged from the hospital for four months, seemed nearly fully recovered, and was behaving normally when she picked up the children to take to her home for the night. Tragically, what Thibault did not tell the Lamberts, was that earlier that evening, State Police had come close to detaining her for a psychiatric evaluation when they found her behaving erratically on the median strip of I-495 in Andover, punching a motorist who had stopped to assist her. Reportedly, Thibault had told a state trooper during that encounter that she was having a “debate between good and evil,” according to State Police documents obtained by the Lambert family. After leaving New Hampshire with her niece and nephew, Thibault crossed the median of I-495, stopped her car in the wrong direction, undressed herself and the two children, and carried them to their deaths in oncoming high speed traffic. According to one eyewitness, Thibault was screaming about religion before she was hit.

A horrible story. What the plaintiffs here must specifically prove, by clear and convincing evidence, is that the defendants deviated from, and hence breached, the standard of care that was legally required by the defendants. This is true in all cases involving allegations of medical malpractice. The “standard of care” that will be applied in this case, will be that of a reasonably prudent psychiatrist (and licensed social worker,) under the same or similar circumstances, and of similar age, intelligence and experience. Assisting the jury in this general legal definition, may be one or more professionally-accredited medical journals or professional guidelines that might be offered into evidence (such as issued periodically by the American Psychiatric Association or American Medical Association.

A suit like this is not a legal “slam-dunk.” The Lamberts will encounter considerable legal hurdles in this suit, notably confidentiality laws that limit what medical providers such as these psychiatrists can disclose to third parties such as themselves, as well a decision last year by the Supreme Judicial Court, which narrowed the duty of medical professionals to protect third parties such as themselves. As a Massachusetts medical negligence lawyer, I think it’s going to be a challenging case, but with two young children killed and a mentally ill woman who committed suicide, it’s top-heavy with emotion and tragedy. And it’s cases like this, that define the legal responsibilities we owe to each other in life every day, and cases like this that stand out.

We serve the following localities: Essex County including Danvers and Beverly; Norfolk County including Braintree, Brookline, Foxborough, Norwood, Quincy, Westwood, and Wrentham; Suffolk County including Boston and West Roxbury; Barnstable County including Falmouth, Hyannis, and Sandwich; Bristol County including Attleboro, New Bedford, and Fall River; Middlesex County including Burlington, Framingham, and Waltham; and Plymouth County including Marshfield, Middleborough, and Plymouth.